163 Journal of Membrane Science & Research HIGHLIGHTS ARTICLE INFO GRAPHICAL ABSTRACT ABSTRACT Performance of Chemically Modifed TiO 2 -poly (vinylidene fuoride) DCMD for Nutrient Isolation and Its Antifouling Properties N.S. Mohd Yatim, K. Abd. Karim, O. Boon Seng* * Corresponding author at: Phone: +6045996418; fax: +6045996908 Received 2015-11-03 Revised 2015-12-23 Accepted 2015-12-29 Available online 2015-12-29 The surface properties of TiO 2 -PVDF nanocomposite membranes were investigated by incorporating different chemically modifed TiO 2 nanoparticles into the poly (vinylidene fuoride) (PVDF) matrix. The nanocomposite membranes were prepared via dual coagulation bath diffusion and the induced phase inversion method. The membrane surface morphologies were investigated by using SEM and AFM and related to the membrane surface energy via contact angle goniometry. The results showed that the average membrane surface pore sizes were increased with the addition of TiO 2 nanoparticles. Nonetheless, the contact angle measurements demonstrated that the hydrophobicity of nanocomposite membranes can be maintained even with the addition of hydrophilic TiO 2 . This observation could be rationalized as surface roughness enhancement. The experimental results demonstrated that the initial fux of acid treated TiO 2 has both higher initial fux and high COD removal due to their induced surface roughness. The TiO 2 -PVDF membranes were found to possess the signifcant bactericidal effect on B. Subtilis compared to the neat membrane even without the presence of UV light. Membrane distillation (MD) DCMD Nanocomposite Chemical modifcation Biofouling journal homepage: www.msrjournal.com Journal of Membrane Science and Research 2 (2016) 163-168 School of Chemical Engineering, Engineering campus, Universiti Sains Malaysia, Seri Ampangan, 14300 Nibong Tebal, Penang, Malaysia KEYWORDS Research Paper © 2016 MPRL. All rights reserved. E-mail address: chobs@usm.my (O. Boon Seng) • PVDF membrane with TiO 2 dosage shows signifcant antibacterial properties. • Addition of untreated TiO 2 impair the membrane porosity and liquid entry pressure. • Acid/alkali treated TiO 2 gave improved performance of the TiO 2 -PVDF composite. membranes, such as SiO 2 [1], Al 2 O 3 [2], Fe 3 O 4 [3] and TiO 2 [4, 5] with the common aims to enhance the performance of the membrane in terms of fux enhancement and antifouling properties. Among the nanoparticles, TiO 2 has received much attention because of its robust physical and chemical 1. Introduction In recent years, the incorporation of inorganic additives into polymeric materials to modify its performance has expanded remarkably for membrane separation. A variety of nanoparticles have been introduced to modify organic